I have a 95 GT 5.0. It started shaking violently for no reason. Did tune up, checked mechanics, everything fine. Engine throws no codes, so I went to get diagnostics, and it said PCM not hooked up to diagnostic. Reset the computer by unhooking battery and cnnecting 2 loose terminals...Ran like a beauty.That was until I shut it off. I had to reset almost every new start, but it would run great when I did. Finally replaced the PCM, now it runs like crap again, even worse...and won't reset. Any input from anyone would be great. Has anyone evr heard of this before? PLEASE HELP ME!!! I WANT MY MUSTANG BACK!!!

Re: Please Help...Car Shakes-Bad PCM, replaced it and it still shakes...

My dad had the same thing with an 86' Capri RS. He thought he had an ignition problem of some sort and replaced every ignition item one by one. He even swapped the PCM- no change.

In the end- there was a small ground wire to the fender apron on the left hand side from the wiring harness that was slightly corroded. It was the ground of some sort- coming from the interior. This fixed everything.

Maybe this is something to check- especially since it does not cost anything if it is. I do not know if the location would be the same on a 95- but it was on my 91'. It was one of the first things I cleaned when I purchased it.

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